1. 集合（set）集合的顯著特點是：里面元素?zé)o重復(fù)
1）set的創(chuàng)建
>>> num2 = {1, 2, 4, 5, 6, 7, 5, 4, 3, 2, 1, 0}
>>> num2
{0, 1, 2, 3, 4, 5, 6, 7}
>>> set1 = set([1, 1, 2, 4, 5, 6])
>>> set1
{1, 2, 4, 5, 6}
2）.add() ? 將一個參數(shù)添加進集合中
>>> num2 = {1, 2, 4, 5, 6, 7, 5, 4, 3, 2, 1, 0}
>>> num2.add(6.2)
>>> num2
{0, 1, 2, 3, 4, 5, 6, 7, 6.2}
3)? .remove()? 將指定元素從原集合中刪除
>>> num2 = {0, 1, 2, 3, 4, 5, 6, 7, 6.2}
>>> num2.remove(6.2)
>>> num2
{0, 1, 2, 3, 4, 5, 6, 7}
4)? .frozenset()? 冰凍集合患民，集合不能改變
>>> num4 = frozenset([1, 2, 3, 4, 5, 3, 2, 1])
>>> num4
frozenset({1, 2, 3, 4, 5})
>>> num4.add(0)
Traceback (most recent call last):
? File "<pyshell#39>", line 1, in <module>
? ? num4.add(0)
AttributeError: 'frozenset' object has no attribute 'add'
